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Valmont Station Update
panorama of valmont power station

Xcel Energy Closure of Valmont Power Station

Xcel Energy plans to close three coal ash impoundment areas at the Valmont Power Station located at 1800 North 63rd Street in unincorporated Boulder County just east of the City of Boulder. The three impoundments scheduled for closure ceased operation in October 2017, with complete closure of the areas expected to be completed by January 2019. The closure of the Valmont Station impoundment areas will be subject to state and federal regulations.

Public Information Session

At a public information session on May 8, 2018, the Board of County Commissioners received an update from Xcel Energy on the status of the Valmont Power Station in relation to the cessation of coal activities at the site.

The meeting has been archived.

Environmental Impact of Power Plants

Coal ash is a byproduct of the combustion of coal used to produce power at power plants. Fly ash, bottom ash, slag, and flue gas desulfurization materials are all terms that represent the different types of coal combustion residuals (CCR). Coal ash is disposed of in wet form in large ponds (surface impoundments), and in dry form in onsite or off-site landfills. Once an impoundment area has reached capacity or is to be closed for other reason, the water is drained and the ponds are dredged. The dredged CCR is then deposited on-site in designated landfills.

Health Risks of Coal Ash

Coal ash contains various components that may be harmful to the environment and to human health. Fly ash and bottom ash contain large amounts of silicon dioxide (SiO2), aluminum oxide (Al2O3), and calcium oxide (CaO), as well as traces of arsenic, cadmium, lead, and mercury. According to the EPA, coal ash contaminants such as mercury, cadmium, and arsenic have been linked to cancer and various other health effects.

State and federal regulations managing coal ash disposal exist to prevent migration of contaminants into groundwater or dispersal into the air. Spills and mismanagement of coal ash have prompted the EPA to impose a Final Rule that provides a comprehensive set of requirements governing the disposal of coal combustion residuals.

Learn more about Xcel Energy’s Closure plan.

Please Note: Boulder County plays no role in the operation or regulation of the Valmont plant. Xcel Energy is a private entity regulated by the Public Utilities Commission and state and federal environmental regulations. However, because the facility lies within unincorporated Boulder County and there is general public interest concerning recent changes at the site, the county commissioners have invited Xcel to come update them and members of the public about the foreseeable use of the site.

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